Dutch association's affair (9)
I believe the answer is:
dalliance
'affair' is the definition.
(I've seen this before)
'dutch association's' is the wordplay.
'dutch' becomes 'd' (common abbreviation).
'association' becomes 'alliance' (I've seen this before).
'd'+'alliance'='DALLIANCE'
(Other definitions for dalliance that I've seen before include "Dawdling" , "A casual romance" , "Flirting" , "Toying - trifling - delay" , "Fling" .)